1. Field of the Invention
The present invention relates to a retightenable and resettable strap lock for luggage or the like, and more particularly to a retightenable and resettable strap lock that can be used to lock a strap for tightening luggage and two pull tabs of the luggage while allowing the strap to be further tightened for reliably tightening the luggage.
2. Description of the Related Art
It is common to carry a big trunk for accommodating clothing. FIG. 13 of the drawings illustrates a conventional buckle device for a trunk having a zipper with two pull tabs A1. A key-operable lock B is mounted to lock the pull tabs A1 together. Nevertheless, it is found that the zipper tends to be expanded outward and thus damaged if the trunk is filled up with too many clothes. A strap buckle is provided to tighten the trunk for solving this problem. As illustrated in FIGS. 14 and 15, the strap buckle includes a male buckle member C, a female buckle member D, a length-adjusting member E, and a strap F. The strap F has an end tied up to a central column E1 of the length-adjusting member E and is extended through an opening C1 of the male buckle member C and two openings E2 of the length-adjusting member E with the other end of the strap F secured to the female buckle member D. The length-adjusting member E may be moved for adjusting the overall length of the strap F before engagement between the male and female buckle members C and D. In order to avoid becoming loosened of the strap F, the length-adjusting member E is designed to have a relatively large friction and thus difficult to move after the male and female buckle members C and D have been engaged with each other. Thus, adjustment in the length of the strap F by means of moving the length-adjusting member E must be accomplished before engagement between the male and female buckle members C and D. Yet, such adjustment to the best tightening effect for the trunk is very difficult to achieve, as the user must estimate the required length of the strap F by sight, which is not so precise such that the strap is either too tight or too loose after each adjustment. The strap might become loosened and the male and female buckle members might be disengaged from each other upon external impingement to the trunk during transportation even if the best length of the strap is found. A further drawback of this conventional method for tightening trunks is that the user must use a lock and a strap buckle that are separate from each other.
The present invention is intended to provide a retightenable and resettable strap lock that mitigates and/or obviate the above problems.